The liturgy (Greek: λειτουργία or λῃτουργία, , from λαός / Laos, "the people" and the root ἔργο / ergon, "work" ) was in ancient Greece a public service established by the city-state whereby its richest members (whether citizens or resident aliens), more or less voluntarily, financed the State with their personal wealth. It took its legitimacy from the idea that "personal wealth is possessed only through delegation from the city". The liturgical system dates back to the early days of Athenian democracy, but gradually fell into disuse by the end of the 4th century BC, eclipsed by the development of Euergetism in the Hellenistic period.
The liturgy was the preferred mode of financing of the Greek city, to the extent that it allowed them to easily associate each public expense with a ready source of revenue. This flexibility makes it particularly suited to the unpredictability of the period. This also explains its widespread use, including in undemocratic cities such as Rhodes. However, no strict uniformity is found in the specific practices of these liturgies, either geographically (from one city to another) or over time (as changing times and circumstances confront the Greek cities).
One can classify liturgies into two main categories. Those associated with the liturgical or agonistic calendar (related to sporting and religious events) are mainly the gymnasiarchia (γυμνασιαρχία), that is to say, the management and financing of the gymnasium, and the choregia (χορηγία), the maintenance of the choir members at the theater for dramatic competitions. There were also many other minor liturgies. The hestiasis (ἑστίασις) was to fund the public dinner of the tribe to which the liturgist belonged; the architheoria (ἀρχιθεωρία) to lead delegations to the four sacred Panhellenic Games;, the arrhephoria (ἀρρηφορία) to cover the cost of the arrhephoroi, four girls of Athenian high society who brought the peplos to the Athena Parthenos, offered her cakes and dedicated white dresses adorned with gold, amongst others. There was considerable creativity in relation to the liturgy, "and with the practicality which characterised their attitude on the subject, the cities were capable of creating new liturgies in accordance with their immediate needs, or of suppressing them temporarily or permanently.". All of these liturgies are part of a religious festival and were recurring (ἐγκύκλιοι).